PRAM

Abstract

The invention relates to a pram or pram frame comprising a pusher bar for pushing the pram or pram frame and at least one force sensor device for detecting a direction or a magnitude of a force or a force component acting on the pusher bar and for detecting a variable derived from said force or force component, in particular a change in the force or force component over time, wherein the at least one force sensor device is designed to measure a force (component) or a variable derived therefrom at least over a vast majority of a horizontal section of the pusher bar, and is designed to measure a force (component) or a variable derived therefrom in at least one, in particular curved or arcuate, transition section of the pusher bar between the horizontal section of the pusher bar and a connecting section of the pusher bar.

Claims

1. A pram or pram frame, comprising: a pusher bar for pushing the pram or pram frame; and at least one force sensor device for detecting a direction or an amount of a force or a force component acting on the pusher bar and for detecting a variable derived from this force or force component, wherein the at least one force sensor device is configured to measure a force (component) or a variable derived therefrom over at least a predominant part of a horizontal section of the pusher bar, or is configured to measure a force (component) or variable derived therefrom in at least one, transition section of the pusher bar between the horizontal section of the pusher bar and a connecting section of the pusher bar.

2. The pram or pram frame according to claim 1, comprising: a pusher bar for pushing the pram or pram frame and at least one force sensor device for detecting a direction or an amount of a force or a force component acting on the pusher bar and for detecting a variable derived from this force or force component, wherein the at least one force sensor device extends at least over a predominant part of a horizontal section of the pusher bar, or extends at least in sections over at least one transition section of the pusher bar between the horizontal section of the pusher bar and a connecting section of the pusher bar.

3. The pram or pram frame according to claim 1, comprising: a pusher bar for pushing the pram or pram frame and at least one force sensor device for detecting a direction or an amount of a force or a force component acting on the pusher bar, and for detecting a variable derived from this force or force component, wherein the force sensor device comprises: a base part, designed to at least partially accommodate at least one sensor unit (sensor); and a sheathing part, which sheaths the base part and the at least one sensor unit at least partially in a handle area of the pusher bar, and which is connected to the at least one sensor unit, wherein the sheathing part is movable with respect to the base part, wherein an intermediate space is present between the base part and the sheathing part, and wherein the at least one sensor unit is designed to detect a movement between the sheathing part and the base part.

4. The pram or pram frame according to claim 1, wherein at least one motor is provided for assisted driving of the pram or pram frame.

5. The pram or pram frame according to claim 1, wherein at least one control device is operatively connected to the at least one force sensor device, such that an output of the at least one force sensor device can be used to control the at least one motor.

6. The pram or pram frame according to claim 3, wherein the control device is designed to control or regulate the output of the at least one motor as a function of the output of the at least one force sensor device in discrete steps or continuously, and is designed in such a way that at least one motor is started when a first threshold of the force or force component or the variable derived therefrom is exceeded, and designed in such a way that at least one motor is stopped or kept at constant power when a second threshold of the force or force component or the variable derived therefrom is exceeded.

7. The pram or pram frame according to claim 1, wherein the sensor device comprises at least two sensor units, which extend at least in sections via a connecting section each and extend adjacent to opposite ends of the horizontal section or extend beyond these ends.

8. The pram or pram frame according to claim 1, wherein the sensor device comprises at least two parts which are movable relative to one another and at least one sensor unit which measures an amount of the relative movement.

9. The pram or pram frame according to claim 1, wherein the first part and the second part are movable relative to each other in at least substantially radial direction and at least substantially in a direction lying in a plane spanned by a forward direction and a vertical.

10. The pram or pram frame according to claim 1, wherein the first part or the second part are fixedly connected to at least one sensor unit.

11. The pram or pram frame according to claim 1, wherein at least one sensor unit is configured to measure an electrical resistance or an electrical resistance change or comprises at least one strain gauge arranged in the horizontal section or transition section, and is configured as a bending beam sensor, wherein a torque exerted on a measuring body acts on at least one strain gauge, wherein one or two strain gauges are stretched and two strain gauges are compressed, wherein four strain gauges are constructed in a bridge circuit to measure resistance changes from the strain gauges.

12. The pram or pram frame according to claim 1, wherein the base part has a straight section and has at least one curved section, and is designed as a solid or hollow profile with a polygonal or round cross section, or the sheathing part has a straight section and has at least one curved section, and is designed as a solid or hollow profile with a polygonal or round cross-section, and the base profile is designed in one piece, or the sheathing part is formed in several pieces from a correspondingly large number of individual parts, each of which may be monolithic in itself, or the sheathing part is formed at least in sections in a transition section by two half shells or the sheathing part surrounds the base part, over an angular range of at least 180°.

13. A method for controlling a pram or pram frame according to claim 1, wherein a force (component) acting on the pusher bar is measured or an amount of a force or a force component acting on a pusher bar or a variable derived from this force or force component is detected.

Description

[0110] The invention is described below on the basis of exemplary embodiments, which are explained in more detail with reference to the figures, wherein:

[0111] FIG. 1 shows a complete pram incl. attachment in perspective view, so that the pusher bar can be seen;

[0112] FIG. 2 shows an exploded view of upper pusher bar section with rounding sheathing part;

[0113] FIG. 3 shows a cross-section of the pusher bar perpendicular to the longitudinal extension of the horizontal section and through the sensor and the first projection of the rounding sheathing part attached to the sensor,

[0114] FIG. 4 shows a longitudinal section through the pusher bar (perpendicular to the horizontal) so that a sensor and a rounding sheathing are visible:

[0115] FIG. 5 shows a longitudinal section through the pusher bar (section in the pusher bar plane) so that a sensor and a rounding sheathing are visible:

[0116] FIG. 6 shows a schematic oblique view of a pram frame according to the invention;

[0117] FIG. 7 shows a side view of the pram frame according to FIG. 6.

[0118] In the following description, the same reference numbers are used for the same and similarly acting parts.

[0119] FIGS. 1 to 5 show a pram frame 10, a pusher bar 11, wheels 12, front wheel struts 13, rear wheel struts 14, an adapter 15, a child-receiving device 16, a motor 17, a control device 18, a horizontal section 101 of the pusher bar 11, a (respective) connecting section 102 of the pusher bar 11, a transition region 103 or transition section of the pusher bar 11, a handle area 104, an intermediate space 105 (see FIGS. 4 and 5) between a base part 110 and a sheathing part 120 of the handle area 104, an edge region 121, a recess 122, a rounding sheathing part 130, a first shell half 131 and a second shell half 132 of the rounding sheathing part 130, a first projection 133, screws 134, a second projection 135, a screw 136, an opening 137, an edge region 138, a third projection 139, a sensor unit 140, and a region 141 for at least one strain gauge. In the assembled state, the third projection 139 preferably engages a corresponding recess 122 of an edge region 121 of the sheathing part 120.

[0120] FIG. 1 shows a pram with a child-receiving device 16. The child-receiving device 16 is connected or connectable to the pram frame 10 via the adapter 15. The child-receiving device 16 has (in the present case) a leg section, a seat section and a backrest section. Alternatively, the child-receiving device 16 can also be designed without a leg section or without such a subdivision into different sections (for example as a reclining insert).

[0121] The pram frame 10 has a pusher bar 11, which in turn has a horizontal section 101 and has (two) connecting sections 102 connecting to the horizontal section 101 via a respective transition region 103. The horizontal section 101 is formed as a horizontal strut. The connecting sections 102 are formed as struts (in the state of use) extending obliquely downwardly (or forwardly) from the horizontal section 101 and can preferably be angled (in particular folded) and/or telescopically varied with respect to their length.

[0122] The pram according to FIG. 1 has four wheels. However, it is conceivable that more or fewer wheels are provided (for example three, in particular one front wheel and two rear wheels). Specifically, two rear wheels and two (rotatable, possibly lockable) front wheels are provided in FIG. 1. The respective pairs of wheels are connected to each other via connecting struts. The struts connecting the wheels are in turn connected to the connecting sections 102 (in particular in an articulated manner) via further struts—front wheel struts 13 and rear wheel struts 14, wherein a single strut may be sufficient for each wheel.

[0123] The transition sections 103 of the pusher bar 11 are curved and preferably form (at least approximately) a quarter circle and/or preferably include an angle of at least approximately 90°.

[0124] Horizontal section 101 and connecting sections 102 are formed extending (at least approximately) at right angles to each other.

[0125] The pusher bar 11, in particular its horizontal section 101 and its transition sections 103, are shown in further detail in FIGS. 2-5.

[0126] FIG. 2 shows a section of the handle area 104, including a section of the horizontal section 101 and one (of two) transition sections 103.

[0127] The sheathing part 120 is provided in the horizontal section 101. This is designed straight in shape. In the transition section 103, the rounding sheathing part 130 comprising the first shell half 131 and the second shell half 132 is arranged. The rounding sheathing part 130 (as well as its shell halves 131, 132) are curved. The rounding sheathing part 130 forms a (bent) sleeve. The sheathing part 120 forms a (straight) sleeve.

[0128] The sheathing part 120 and the rounding sheathing part 130 sheath the base part 110. The sheathing part 120 is shifted to the right relative to the base part 110 in FIG. 2, so that the sensor unit 140 located inside the sheathing part 120 and the rounding sheathing part 130 can be seen. In the assembled state, the two openings in the sheathing part 120 shown at the left end in FIG. 2 are in register with the recesses or openings or the screws 134 shown at the left end of the sensor unit 140 (see also FIGS. 3 and 4).

[0129] As can also be seen in FIGS. 3 and 4, rounding sheathing part 130 or its half-shell 132, sheathing part 120 and sensor unit 140 are connected via the (here exemplarily two) screws 134. In general, another fastening means (in a different number, for example also one or more than two) may also be provided for this purpose.

[0130] The two half shells 131, 132 are in turn connected to each other via the second projection 135 (with internal thread) and the screw 136. Other fastening or connecting devices are also conceivable here. However, a detachable fastening is preferred.

[0131] An opening (channel 111) may be provided in the base part 110 that is (slightly) larger than the second projection 135 to prevent an unwanted connection between the rounding sheathing part 130 and the base part 110.

[0132] Specifically, the second shell half 132 includes a first projection 133 extending between the sheathing part 120 and the base part 110 and having two openings through which the screws 134 may be inserted.

[0133] The first projection 133 adjoins an edge region 138 of a main body of the second shell half 132 (see FIGS. 3 and 4), wherein the edge region 138 of the main body of the second shell half 132 additionally adjoins, preferably directly, in particular positively, an edge region 121 of the sheathing part 120.

[0134] An opening 137 is provided for passing the screw 136 through the second shell half 132 (see FIG. 3).

[0135] The first shell half 131 includes a third projection 139 (see FIG. 2) that is engageable with the sheathing part 120, particularly with a recess 122.

[0136] The sensor unit 140 can itself function according to the principle of a strain gauge and/or (see FIG. 4) have an area 141 in which a strain gauge (not shown in detail) can be arranged. If a pressure is now applied to the sheathing part 120 and/or the rounding sheathing part 130, the sensor unit 140 or an optional strain gauge 141 (or, as the case may be, several strain gauges) can be correspondingly stretched and/or compressed (due to the distance between the sensor unit 140 and the respective sheathing part 120 or rounding sheathing part 130, which is provided at least in sections). This stretching and/or compression can then be evaluated accordingly to determine whether sheathing part 120 and/or rounding sheathing part 130 has been gripped by a user.

[0137] For example, the sensor unit 140 may be configured to measure an electrical resistance or a change in electrical resistance. The sensor unit 140 may include at least one (optionally two, three, four, or more) strain gauges. The strain gauges may be disposed in the horizontal section and/or transition section. The sensor unit 140 may be configured as a bending beam sensor, preferably wherein a torque applied to a measuring body acts on at least one (e.g., four) strain gauges. For example, one or two strain gauges may be stretched and one or two strain gauges may be compressed. Specifically, four strain gauges may be constructed in a bridge circuit to measure resistance changes of the strain gauges.

[0138] FIG. 6 shows a pram frame according to the invention in a schematic oblique view. The arrow F.sub.d indicates a downward force acting on a handle 23 (in the horizontal section). The arrow F.sub.u indicates an upwardly directed force acting on the handle 23. The arrows F.sub.iat indicate sideways directed forces. The handle 23 is pivotally mounted relative to a lower section of the pusher bar 11.

[0139] Specifically, the handle 23 can be pivoted (and engaged) in various positions to perform a height adjustment of the handle 23.

[0140] A pivotable bearing 22 (with corresponding joints) is provided between the pivoting handle 23 and the lower section of the pusher bar 11.

[0141] The (entire) pusher bar 11 is again preferably pivotally mounted on a pivotable bearing 21 on a main body of the pram frame (in particular, to allow the pram frame to be folded).

[0142] Alternatively or in addition to an arrangement of the sensor device according to FIGS. 1 to 5, a sensor device/sensor devices can be provided on the pivotable bearing 21 and/or on the pivotable bearing 21 in order to detect a force of a user (in particular F.sub.u and F.sub.d) acting on the handle 23. Furthermore (see FIG. 7), a forwardly directed force F.sub.f as well as a backwardly directed force F.sub.r can preferably be detected with the respective sensor device. In wheel hubs 31, motors can preferably be placed (not shown in detail). Alternatively, motors can be placed on an axle 32 (in particular on sections of the axle that are adjacent to the wheel hub 31).

[0143] At this point it should be pointed out that all the parts described above, taken individually and in any combination, in particular the details shown in the drawings, are claimed to be essential to the invention. Modifications thereof are familiar to those skilled in the art.

LIST OF REFERENCE SIGNS

[0144] 10 Pram frame [0145] 11 Pusher bar [0146] 12 Wheels [0147] 13 Front wheel struts [0148] 14 Rear wheel struts [0149] 15 Adapter [0150] 16 Child-receiving device [0151] 17 Motor [0152] 18 Control device [0153] 21 Pivotable bearing [0154] 22 Pivotable bearing [0155] 23 Handle [0156] 31 Wheel hub [0157] 32 Axle [0158] 101 Horizontal section [0159] 102 Connecting section [0160] 103 Transition region [0161] 104 Handle area [0162] 105 Intermediate space [0163] 110 Base part [0164] 111 Channel [0165] 120 Sheathing part [0166] 121 Edge region [0167] 122 Recess [0168] 130 Rounding sheathing part [0169] 131 First shell half [0170] 132 Second shell half [0171] 133 First projection [0172] 134 Screws [0173] 135 Second projection [0174] 136 Screw [0175] 137 Opening [0176] 138 Edge region [0177] 139 Third projection [0178] 140 Sensor unit [0179] 141 Region for strain gauges